This reworks the selection logic to prevent any possible index out of
bounds exceptions by clamping the start and end points before doing
anything else with them when converting selections to spans.
This also fixes a bug where semantic selections would not automatically
expand across double-width characters.
Fixes#2486.
This is a large refactor of the config parsing structure, attempting to
reduce the size of the file a bit by splitting it up into different
modules with more specific purposes.
This also fixes#2279.
This switches our own `copypasta` crate with the more standardized
`clipboard` library, which allows us to get rid of the `xclip`
dependency on X11.
Additionally, this lays the foundation for native Wayland clipboard
support once the clipboard crate is updated (or a fork is created).
Fixes#5.
Christian Duerr